Summary of Significant Accounting Policies	9 Months Ended
Sep. 30, 2021
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	1. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Basis of Consolidation and Variable Interest Entities DESC has determined that it has a controlling financial interest in each of GENCO and Fuel Company (which are considered to be VIEs) and, accordingly, DESC's Consolidated Financial Statements include, after eliminating intercompany balances and transactions, the accounts of DESC, GENCO and Fuel Company. See Note 2 to the Consolidated Financial Statements included in DESC’s Annual Report on Form 10-K for the year ended December 31, 2020 for a description of GENCO and Fuel Company. Effective January 2021, DESC purchases shared services from DES, an affiliated VIE that provides accounting, legal, finance and certain administrative and technical services to all Dominion Energy subsidiaries, including DESC. DESC had previously purchased such services from DESS, an affiliated VIE, that had provided such services to all SCANA subsidiaries. DESC has determined that it is not the primary beneficiary of DES as it does not have either the power to direct the activities that most significantly impact its economic performance or an obligation to absorb losses and benefits which could be significant to it. See Note 12 for amounts attributable to affiliates. Significant Accounting Policies There have been no significant changes from Note 2 to the Consolidated Financial Statements in DESC's Annual Report on Form 10-K for the year ended December 31, 2020, with the exception of the item described below. Asset Retirement Obligations In the third quarter of 2021, DESC revised its estimated cash flow projections associated with certain gas distribution pipeline AROs. As a result, DESC recorded a $23 million decrease to AROs with a corresponding $20 million decrease to utility plant, net and the remainder recorded as a decrease to regulatory assets.

Summary of Significant Accounting Policies

9 Months Ended

Sep. 30, 2021

Summary of Significant Accounting Policies

1. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Basis of Consolidation and Variable Interest Entities

DESC has determined that it has a controlling financial interest in each of GENCO and Fuel Company (which are considered to be VIEs) and, accordingly, DESC's Consolidated Financial Statements include, after eliminating intercompany balances and transactions, the accounts of DESC, GENCO and Fuel Company. See Note 2 to the Consolidated Financial Statements included in DESC’s Annual Report on Form 10-K for the year ended December 31, 2020 for a description of GENCO and Fuel Company.

Effective January 2021, DESC purchases shared services from DES, an affiliated VIE that provides accounting, legal, finance and certain administrative and technical services to all Dominion Energy subsidiaries, including DESC. DESC had previously purchased such services from DESS, an affiliated VIE, that had provided such services to all SCANA subsidiaries. DESC has determined that it is not the primary beneficiary of DES as it does not have either the power to direct the activities that most significantly impact its economic performance or an obligation to absorb losses and benefits which could be significant to it. See Note 12 for amounts attributable to affiliates.

Significant Accounting Policies

There have been no significant changes from Note 2 to the Consolidated Financial Statements in DESC's Annual Report on Form 10-K for the year ended December 31, 2020, with the exception of the item described below.

Asset Retirement Obligations

In the third quarter of 2021, DESC revised its estimated cash flow projections associated with certain gas distribution pipeline AROs. As a result, DESC recorded a $23 million decrease to AROs with a corresponding $20 million decrease to utility plant, net and the remainder recorded as a decrease to regulatory assets.